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By C Fearon

This paper discusses the implementation of an underground rail haulage system during a major expansion of the Olympic Dam mine in 1998. The factors affecting the selection of rail haulage are discussed and details are provided on the rail system, which is designed to transport more than 10.5 million tonnes per annum (Mtpa). The reliability of the system during commissioning is discussed, including the decision to manufacture a ædummyÆ locomotive in order to keep the system operational. Finally, reliability improvements made both during and after commissioning are discussed with comments provided on the effectiveness of the system as it operates today.

Jan 1, 2005

The ore reserves of the Frieda porphyry copper prospect in Papua New Guinea have been estimated using kriging and an alternative method. Only very erratic variograms could be obtained from the raw data and thus it can be expected that kriging variances will be unrel- iable. The frequency distributions of the two sets of estimates show expected differences and the resulting mineable reserves show similar expected differences. More drilling and the use of disjunctive kriging are needed to produce reliable estim- Ates.

Jan 1, 1979

While the new Minister of Economic Development sends his apologies at being unable to speak at this Conference, I am delighted to present on his behalf. The Ministry of Economic Development is not only responsible for managing the Crown mineral estate, but also for developing initiatives and policies to promote regional economic development and for managing the GovernmentÆs broader economic development strategy. IÆd like to talk to you today about the critical links that need to exist between these three areas.   I am going to start with a question for all of you. What do these towns have in common? +        Waiuku, +        Thames, +        New Plymouth, +        Nelson, +        Greymouth, +        Arrowtown, +        Reefton, +        Palmerston, and +        Dunedin.   The answer is minerals. These towns were nearly all founded on the back of minerals and mining. In the case of Greymouth it was gold that brought the people to the mouth of the Grey River and it is coal that sustains the town.   In 1870 the town of Shortland had 20 000 people, 90 hotels and was twice the size of Auckland. We now know Shortland as Thames, and of course Auckland is considerably larger. One wonders whether the good folk of Shortland suffered from ætraffic jamsÆ with 90 pubs to navigate between. Gold mining in the Aorere River near Collingwood led early entrepreneurs to develop the land surrounding Nelson as a food basket to sustain the mining population. Nelson is still thriving on this legacy today. The town of Palmerston was founded in 1862 as a stopping point for gold miners heading into central Otago. The gold rush made Dunedin New ZealandÆs first highly industrialised city. Reefton on the West Coast was the first town in New Zealand to have electric lights and in the recent past we were wondering whoÆd be left to turn them off. New Plymouth, and Waiuku are still known as energy and mining centres.   By contrast once thriving towns like Capleston, Canvastown and Blackball are just names on a map now, and at the extreme you have places like Waiuta which has been reclaimed by the West Coast forest. Queenstown was built off the back of the gold rush, but by 1900 with the gold gone, only 190 people lived there yet Queenstown has managed to rebuild itself thanks to some other stunning natural assets. These examples help illustrate three key points that I am sure will each be extensively linked with our minerals and mining industries. First, NZÆs development and that of its regions has been, and continues to be, inextricably linked with our minerals and mining industries.   Second, things change. Sectors, regions and countries must continually adapt and improve if the are to avoid the fate of the Waiutas of this world. And third, the development challenges faced by NZ and its mining industry in the 21st century are vastly more complex than in the past. Governments and industry alike must balance and respond to a range of domestic and international environmental, cultural, economic and other interests and considerations. If you thought of your industry as æjust digging holes in the groundÆ then you may as well simply stick your head in one!

Jan 1, 2005

The issue of fine coal and tailings dewatering has become of increasing concern to many coal preparation operators, both in Australia and overseas due to a variety of factors. Increasing mechanisation and mining of thinner seams over the past decades has resulted in an increasing amount of fines generation while increasing international trade in coal and tighter environmental constraints on tailings disposal have resulted in the production of these same fines to be an increasing problem. However, technology to date has not always been able to supply a cost-effective solution to the handling of these fines in an efficient and environmentally benign manner. This paper will review the key issues associated with the dewatering of fine coal and tailings, will describe the major current practices and constraints, and finally will indicate alternative technologies that may have to be considered in the near future. For the purpose of this paper, "fine" coal is described as that material less than 0.5 mm in diameter (as this is the most common cutpoint between various plant circuits in Australian practice), although the technological constraints are very much dependent upon the fraction less than 45 micron. The amount of minus 0.5 mm material fed to plants varies, depending upon the type of coal and mining operation, but in Australia may range from less than ten per cent to greater than 30 per cent of the feed in higher rank coals.

Jan 1, 1991

By Roxborough F. F

The ability of the Australian minerals industry to successfully manage the changes and challenges that face it in the 21st century depends ultimately on the quality of its human resources. Mining engineers have a vital role in this regard. The education and training that universities are currently giving to mining engineers is under challenge and needs to be reassessed in the light of industry directions for the 21st century. At one extreme is a push for a `finished product' graduate, up and running in `the flavour of the month' issues. At the other extreme are moves to reduce face-to-face university teaching hours and return to the time honoured university concept of `reading' for a degree. The lessons of Mourn make it apparent that neither approach is appropriate to the industry's future needs (Windridge, 1996). Basic knowledge gets rusty with time and new skills need to be learned. In order to conduct mining operations safely, productively and competitively, mining engineers must now accept the need to be prepared for continuing professional development as a career imperative. The concept of being professionally or statutorily qualified for life is no longer valid. This calls into question the purpose, content, structure and mode of delivery of university courses, all of which need to engender the principle and facilitate the cause of continuing professional development. This paper presents a model which aims to deliver a quality assured university education for mining engineers for the 21st century at undergraduate, postgraduate and professional level. The model extends beyond traditional university boundaries to match industry requirements to international best practice. It is based on collaborative alliances and innovative presentation modes which will provide industry access to undergraduate and postgraduate course elements presented by a broad range of national and international academic and industry authorities. It offers the prospect for preserving the best of university ideals in higher education, for developing and maintaining programs of direct relevance to industry needs and for a structured involvement in the continuing professional development of mining engineers.

Jan 1, 1997

Optimising drill performance has always been a primary goal of drilling and blasting managers. Improving drilling rates and utilisation will ultimately drive the cost per foot or metre downward. Additionally, more consistent production will ensure shovel or dragline performance goals are met and the chances of machine idle time is minimised. Over the past 20 years, many studies have examined rotary drilling factors and performance issues. In most cases a common theory points to energy input versus drilling output. Indexes such as specific energy and total work energy have been -developed to quantify the drilling process. As general engineering principles dictate, energy is required to drill rock by overcoming compressive and shear strengths. Concurrently, the greater the energy input, the faster the penetration output. Therefore, by examining the basic drilling energy parameters, optimisation is possible. The principles of rotary drilling are driven by five factors. When optimised individually and as a system, drill performance will improve. Most recent studies all agree that a performance relationship exists between bit load, bit rotation, and hole flushing. Additionally, proper bit selection and most of all, the operator, can have a tremendous effect on drill productivity. By analysing these factors and establishing the best case scenario, an overall drilling system can be engineered to match the mining characteristics. Furthermore, by balancing these factors, a lower cost will be achieved through increased production rates, maintenance costs, and effective drill utilisation.

Jan 1, 1995

This paper examines the reform of mining legislation over recent years, the establishment of new Crown land management agencies, and the role of the Crown and environmental groups in nature conservation in New Zealand. It describes the relationship of the minerals industry to the Department of Conservation and environmental groups over recent years, and the prospects for mineral development on the Conservation Estate in future.

Jan 1, 1995

New Zealand's obligations under Kyoto protocol New Zealand's economic and emissions profile Use of energy and electricity generation in New Zealand World energy supply Coal's rule in the world today Coal and New Zealand Future energy needs in New Zealand Clean coal technologies

Jan 1, 2002

By Sivell W

We discuss the origin of the Patuki ophiolite complex and the Dun Mountain ultramafics of Middle Permian age in Nelson, New Zealand. It is shown that the Patuki volcanics have strong affinities with tholeiites of mid ocean spreading ridges transitional to alkaline basalts similar to those from fracture zones and ocean islands. At D'Urville Island, typically pillowed alkaline basalts enriched in rare light rare earth elements (LREE) - ophitic spilites - are associated with LREE-depleted (N-MORB-like) tholeiitic spilites with intergranular textures. The metabasalts are associated with a wide variety of sediments, and with sediments are intruded by conformable sheets of serpentinite. Coarsely crystalline mafic and plagiogranitic rocks signify vents and magma chambers, and we propose that the group developed as ocean crust from a slowly spreading mid-ocean ridge, transform association, overwhelmed at intervals by volcaniclastic sediment. Detailed mapping at a scale of 1:5000, and stratigraphic and geochemical development and structural coherence, show that the group is not melange in the Franciscan sense. The Dun Mountain Group, of serpentinites, peridotites, dunites, gabbros and other rocks, intruded the upper Patuki Group as a linear series of aligned pods and sheets. They carried up with them tectonic inclusions of older rock, which were metasomatised, and altered wall-rock, and one low angle dike passed several hundred metres into overl~ing sediment, at moderate temperatures (500 C). The rocks did not act as a floor (and alleged source) for the Patuki, but partly post-dated and were emplaced into Patuki.

Jan 1, 1987

In current mining practices it is desirable to bring about a substantial increase in both rate of face advance and productivity, thus compelling the mine engineer to consider better and more productive ways of mining. Transportation plays a vital role in achieving improved productivity. This paper focuses on horizontal transportation systems. Horizontal transportation is defined from the shaft station area to the end of the stope cross-cut. Traditionally, horizontal transportation is inefficient in comparison to vertical transportation efficiencies and accounts for a high proportion of South African mine accidents. Thus, the role of horizontal transportation has been investigated in detail, as it offers the greatest chance for improvement. The purpose of the paper is to provide a best practice guideline for the design of horizontal underground transport systems. It is intended that the document be used by mine designers and planners as an aide memoir during the design process and benefit may well be gained from retrofit and reorganisation activity. The paper looks at transport systems suitable for deep level gold mining in South Africa and evaluates such items as management, scheduling, and haulage systems. Current transportation systems for personnel, material and rock transportation are evaluated, gaps in technology highlighted, and recommendations made.

Jan 1, 2003

By Harraway D. H, Draper N

The association of graphite with a fine grained pyrite in the Mount Isa lead-zinc ore was investigated from mineralogical and metallurgical standpoints. The pyrite has been partially or completely replaced by galena and to a less extent by sphalerite, pyrrhotiteand chalcopyrite with the retention of graphite films or inclusions. During lead flotation the graphite imparts a spontaneous flotability to all associated minerals, resulting in a low grade fraction, which we call the carbonaceous fraction, floating with and diluting the lead concentrate. In times of low metal prices this fraction seriously reduces the economic value of the lead concentrate. A flotation procedure was developed to upgrade the carbonaceous fraction separately, producing an economic concentrate and a tailing.INTRODUCTIONThe lead concentrate produced from Mount Isa ores can vary from 20 to 50 per cent lead, depending on the locality in the mine from which the ore is obtained. Variations of this order are independent of ore grade and lead recovery. The large variation is related to the presence in the ore of a variable fast floating low grade fraction known locally as the carbonaceous fraction because of its association with graphite. During conventional lead flotation with sodium ethyl xanthate the carbonaceous fraction floats rapidly and unselectively with normal Mount Isa galena.The paper discusses mainly the examination and treatment of an average carbonaceous fraction, defined here as the fast floating material in the mill feed of late 1956. The ore was drawn from the Mount Isa Black Star orebodies. The fraction represented about 5 per cent of the total ore...

Jan 1, 1961

The world is getting flatter through internet, mobile phone technology, relatively low cost travel, massive outsourcing of manufacturing to China and the transfer of company backroom operations to India. In the iron and steel industry, however, things will remain relatively the same with slow gradual improvements in technology; only the geographic location of plants may change over time. Or will it? The blast furnace smelting process has remained largely unchanged since 1828 when James Neilson came up with the idea of preheated air being delivered to the tuyeres. Likewise, oxygen steelmaking that takes molten iron from such blast furnaces has remained conceptually unchanged since Sir Henry Bessemer invented an air-based system in 1856. These two processes are the core of integrated steel mills that we know today. Typically such mills consist of coke ovens, sinter plant, blast furnace, oxygen steelmaking, continuous caster, rolling mills and metal coating lines. In the intervening 150 years the only real disruptive technology to the integrated steel mill has been the minimill. Based on the use of the electric arc furnace (EAF), in conjunction with a continuous caster and rolling mill, the term minimill is used because steel products are produced at down to one-tenth the scale required for economic operation of an integrated mill, with the EAF producing molten steel using largely scrap steel as its feed, as against transforming coal to coke (coke ovens), iron ore, coke and limestone into molten iron (blast furnace) and molten iron to steel (oxygen steelmaking). There are, however, a number of technologies in development that may cause a paradigm shift in the way steel products are produced and perhaps push the evolution of the minimill as a disruptive technology. Two examples are direct iron smelting, where iron is produced in a matter of seconds by injection of ironmaking feed materials into a molten bath, and thin strip casting, where molten steel is cast into 2 mm strip or less, in similar time. Both have Australian connections. A leading iron smelting technology is the HIsmelt« process, which has its first commercial application at Kwinana, Western Australia, where a joint venture of international parties, consisting of Rio Tinto and the Nucor, Mitsubishi and Shougang corporations, are in the stage of ramping up commercial production. The leading strip casting technology is the Castrip« process that arose from development work done by then BHP Steel, with IHI of Japan, at Port Kembla, New South Wales in the 1990s. Nucor followed this work up, building the first commercial plant for the technology at its Crawfordsville site in Indiana in 2001 and has recently announced an intention to build a second plant in the USA. While both technologies are only into the early stages of commercialisation they are likely to change the face of iron and steelmaking as we know it over the next 20 years. This paper elaborates on the technology of the two processes, why they could change the face of the iron and steel industry forever, what might drive the rapid change and what the changes may look like.

Jan 1, 2006

By Carras S, Kelsey P, Caccetta L

An important problem in open pit mine planning is that of detennining the optimum ultimate pit limits of the mine. These limits are that contour which is the result of extracting the volume of material which provides the total maximum profit while satisfying certain practical operational requirements such as safe wall slopes. The determination of the optimum pit contour provides information that is essential in the evaluation of the economic potential of the mineral deposit. A number of optimisation techniques are available for determining this contour with the Lerchs-Grossman and the Network Flow methods being the most favoured. Unfortunately, direct application of these techniques to large ore-bodies may cause considerable difficulties because of the computational time and storage requirements. In this paper, we present a strategy for resolving these problems, and the associated pit design software PITOPTIM (incorporating a fast network flow technique) and a data reducer, BOUND. The results presented highlight the speed and power of the software package rivalling the popular Lerchs-Grossman technique. An application of the software for a sensitivity analysis is also presented and discussed.

Jan 1, 1991

By Rashkovski GB

Until recently amalgamation has been the main process forextracting large gold particles from gravity concentrates obtainedduring the dressing of ores and placer gold deposits.Development of new technology for treating the gravityconcentrates was necessary because of the harmful effect ofmercury on subsequent production processes and theenvironment. The harmful effect of mercury is particularlyevident in the resin-in-pulp process that is widely applied inRussia.

Jan 1, 1993

Infrastructure is defined as all those parts of a mining development which are not directly concerned with mining and mineral processing. Infrastructure is of significant and growing importance in the overall develop- ment of mines, and the costs could be critical in determining the viability of a project. Prior to_project authorisation, feasibility studies are required, often in considerable detail, to determine costs with adequate reliability. It is necessary that the Engineer should be adequately briefed for carrying out these studies and that good liaison and communication with the Owner be maintained. Methods, costs, order of accuracy, and some special requirements of these studies are discussed. After project authorisation, rapid im- plementation of the proposals is generally desired. A suggested organisation and method for this implementation is presented and dis- cussed. Comments on fees, and particular points in the relationship between Owner and Consulting Engineer are given. Particular reference is made to differences in conditions compared with public works projects. Realistic attitudes of mind towards environmental matters, industrial relations, and contractual relationships are advocated.

Jan 1, 1974

A continuous casting machine, of the Concast curved mould design casting billets in four strands, was commissioned at the Newcastle Works of The Broken Hill Proprietary Co. Ltd., in November, 1967. Quality assessment of early casts from this plant indicated that steel cleanliness was sometimes inferior to that of equival- ent ingot cast steel. Extensive trials to develop a modified deoxidation technique were not successful in improving clean- liness to the desired level. A "contra-flow" gas shroud, to cover the steel stream between the tundish and the mould, was developed, and proved successful in achieving the required levels of product cleanliness. The inclusion content of six grades of steel ranging in carbon content from 0.10 to 0.70 per cent is examined, and an attempt is made to explain theoretically some of the results obtained.

Jan 1, 1972

The exploration industry generally has a low opinion of the quality of the service supplied to it by government departments. In particular, the academic research-related emphasis of the Bureau of Mineral Resources (BMR) and the relatively low level of explora- tion assistance offered by several Mines Departments are of concern. In a number of areas of geoscience research, the industry perceives a mixup of priorities and a lack of understanding on the part of governments as to its needs. While government's sights are, and should be, set on the future needs of the community at large, the industry doubts that government budget allocations to the BMR and Mines Departments are either large enough or being cost-effectively spent. This is certainly the case for such areas as exploration assist- ance, provision of basic exploration data, and applied geoscientific research. On balance, the exploration industry's perceptions are misguided in a number of respects because of a lack of communication with government. However, this reinforces the need for changes in the manner in which govern- ment departments communicate with industry and, in particular, the criteria upon which research priorities are based. At a time of contracting oil and mineral exploration expenditure, and near-record levels of geoscientist unemployment, the government's role is critical and should be open to question.

Jan 1, 1986

The Directional Drill Monitor (DDM) is an advanced instrument for real time in hole surveying. It was developed by Du Pont (Australia) to suit Australian gassy coal mining conditions. The instrument consists of three units: i. Down hole transmitter ii. Acoustic transducer iii. Data receiver processor unit (i.e. up hole unit). This paper describes the function of each unit in detail and highlights the importance of the DDM in long hole drilling efficiency. Surveying is carried out independent of hole depth. Each survey takes 2-3 minutes to complete, the frequency of surveying to control borehole trajectory is determined by the accuracy required for a particular hole.

Jan 1, 1992

By Lane D. P, Malone J. G

The slag fuming furnaces are the major bottleneck in the BHAS zinc production flowsheet. Intensification of the fuming process could significantly reduce this production restriction. Oxygen enrichment was proven to be a means of intensifying the fuming process. This procedure resulted in higher slag bath temperatures, and development work was undertaken towards obtaining accurate slag bath temperature measurement and control. Slag bath temperature measurement techniques were evaluated, with infra red optical pyrometry established as the system with the most potential for continuous temperature measurement and control. Oxygen enrichment resulted in a zinc production capacity increase of 1 000 tonnes per year. An oxygen enrichment technique was developed which both minimized the risk of furnace damage and made the most efficient use of the enrichment oxygen.

Jan 1, 1989

By Runge IC

The mine planning process is reviewed and appropriate software considered in terms of "line process" or "support function". The mine planner's requirements of a geological model and the elements of and requirements of a computerised mine planning system are all discussed. The use of "support" software for mine planning is considered and general rules for its development are given. Important changes involved in implementing a computerised mine planning program are listed.

Jan 1, 1983